Microclimate research under MODEMA project

In April 2026, the second potential evaporation measurement campaign within the MODEMA project was conducted. The project focuses on investigating agroforestry systems (AFS) and their potential for climate adaptation and mitigation, as well as the provision of additional ecosystem services. As part of the project consortium, the Soil-Plant Systems Department at BTU Cottbus–Senftenberg specializes in both bioenergy wood production in so-called Short Rotation Alley Cropping Systems (SRACS), involving fast-growing trees and shrub vegetation, and the investigation of microclimatic alterations caused by AFS.

Potential evaporation (PE) represents the potential water loss under given microclimatic conditions through evaporation from a surface with unlimited water availability. It can serve as an indicator of the water-use efficiency of a system and may be used for further estimations of actual water loss. Potential evaporation was measured using Piche evaporimeters: glass tubes (Fig. 1) filled with water and sealed at the lower end with filter paper, thereby imitating an evaporating soil surface. Data collection and maintenance, including refilling of the tubes, were carried out every morning. Continuous measurements over periods of four to five days were conducted at each of three study sites: two agroforestry systems in Lower Saxony and one in Brandenburg.

Each site was equipped with eight weather stations (six within the agroforestry system and two on the reference field), measuring air temperature, relative humidity, global radiation, wind parameters, precipitation, and soil microclimatic variables. Each station within the agroforestry systems included five replicates, while five additional replicates were established on the corresponding reference fields (Fig.2).

Ultimately, the combination of potential evaporation and microclimatic data may enable the development of a model for estimating water loss under microclimatic conditions influenced by agroforestry systems, as well as for comparing water loss dynamics between agroforestry and conventional agricultural systems.